How can I animate the amount of the "shape match" constraint property?

[Masoud]

Hi guys,

I need to animate the amount of the "shape match" constraint property.

I know that it must be done inside the solver's dynamic network, using the Vellum Constraint Properties, but I don't know how 

 

Thanks for helping.

Vellum_ShapeMatch.hip

[Atom]

It's the same value as stiffness for the cloth node.

if(@Frame>30){stiffness = 0.0;}

 

[Masoud]

Hi Atom,

Do you mean I have to put this in the "VEXpression" part of the "Vellum Constraint Properties"?
Actually, I would like to animate it by keyframes...

Edited March 2, 2023 by Masoud

[Atom]

Before the mesh becomes cloth, drop down a point wrangle. Add a float value to the interface. Place your keyframes there.

f@my_attrib_name = chf("animate_me");

After the wrangle, drop down a NULL named OUT_ATTRIBS.

Dive into the solver to configure the vellumconstraintproperties. On the inputs tab change one of the non-used inputs to fetch from sop, OUT_ATTRIBS.

Then it's just a vex transfer of the animated value to the attribute you want to drive.

float my_animated_value = point(1,"my_attrib_name",@ptnum);
stiffness = my_animated_value;

Don't forget to turn on the check box for the Stiffness value so the code can overwrite it.

Edited March 2, 2023 by Atom

[Masoud]

Thank you Atom, but should I add "@type=pressure" in the group tab !?

And, I don't know why the results are not the same, when I modify the stiffness parameter in the ShapeMatch node, and when I overwrite it by the  VEXpression using vellumconstraintpropertiese !! 

Edited March 3, 2023 by Masoud

[Atom]

There is a similar problem at this link, with an example file. It's MOPs related, but illustrates how to pull in an animated attribute.

https://www.sidefx.com/forum/topic/87419/

[Masoud]

Thank you.